Theoretical study on the hydrogenation of furfural for furfuryl alcohol production over low Ni modified Cu catalysts

Abstract

Cu-based catalysts are efficient for the upgrading of biomass-derived furfural (FF) to produce furfuryl alcohol (FOL), and a low amount of Ni doping is promising to improve the catalytic performance. Herein, Cu (111), Cu7Ni (111), and Cu3Ni (111) catalyst models were constructed. Density functional theory (DFT) calculations were applied to explore the effects of Ni on the FF hydrogenation mechanism by analyzing the FF adsorption configurations, adsorption energies, electronic structures of the adsorbed FF and the catalyst surfaces, as well as reaction pathways and energy barriers of FF hydrogenation. Ni doping promotes the charge transfer between the catalyst surface and FF, thus enhancing the adsorption capacity of the catalyst. The H2 dissociation ability can also be enhanced by the Ni modification. In the initial hydrogenation process, the aldehyde group of the adsorbed FF is easy to hydrogenate and thus contributing to the selective production of FOL. With the increase of the Ni amount, the competitiveness of the hydroxyalkyl intermediate (F–CHOH) involved pathway increases according to the gradually widened energy barrier gaps among the competing pathways. All in all, the Cu3Ni (111) catalyst has the best hydrogenation activity with an energy barrier of 8.99 kJ/mol.